EP0450841A2
Expired / Lapsed
EP
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Video control system
Assignee: Verizon Laboratories Inc
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Filing: 1991-03-25
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Granted: —
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Expires: 2011-03-25
Abstract
Abstract A video control system includes a central facility (11) and a terminal (10). Video program means provided the terminal with a video program including a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video signal according to the random digital code. The terminal (10) includes means (22) for sending the program identification data to the central facility (11). The central facility includes a data base (19) for storing and retrieving at least one code encryption key corresponding to the program identification data and means (20) for sending the code encryption key from the central facility (11) to the terminal (10). The terminal (10) further includes means (22) for receiving the code encryption key from the central facility, decrypting means (23) for decrypting the encrypted digital code of the first frame in accordance with the code encryption key and means (24) for transforming the unintelligible video signal of the second frame to the intelligible video signal using the decrypted random digital code. The video program means may transmit the program to said terminal (10) or be located at the terminal (10) for playing a video recording medium storing the program.
Inventors
- 👤 Stephen S. Walker
- 👤 Clarence M. Sidlo
- 👤 Melvin J. Teare
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 21:39
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/167; H04N7/1675; H04N21/00; H04N21/20; H04N21/25; H04N21/254; H04N21/2543; H04N21/266; H04N21/26613; H04N21/40; H04N21/43; H04N21/432; H04N21/4325; H04N21/433; H04N21/4334; H04N21/60; H04N21/65; H04N21/658; H04N21/6581; H04N7/162; H04N7/165
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
178 words
A video system comprising: a central facility; a terminal; and video program means for providing to said terminal a video program including a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video-signal according to said random digital code; said terminal including means for sending said program identification data to said central facility; said central facility including a data base for storing and retrieving at least one code encryption key corresponding to the program identification data and means for sending said code encryption key from said central facility to said terminal; said terminal further including means for receiving the code encryption key from said central facility, decrypting means for decrypting the encrypted digital code of said first frame in accordance with said code encryption key and means for transforming said unintelligible video signal of said second frame to said intelligible video signal using the decrypted random digital code.
Claim 2
Dependent Claim
54 words
The system of claim 1 wherein a plurality of code encryption keys are used for one program, and wherein a desired code encryption key is selected from said plurality of code encryption keys in accordance with code encryption key identification data corresponding to the random digital code encrypted with said desired code encryption key.
Claim 3
Dependent Claim
21 words
The system of claim 1 or 2 wherein said video program means is means for transmitting said program to said terminal.
Claim 4
Dependent Claim
14 words
The system of claim 3 wherein said means for transmitting is a CATV system.
Claim 5
Independent Claim
122 words
The system of any one of claims 1-4 wherein: said terminal further includes means to store terminal identification data and a terminal specific encryption key; and means to send to said central facility said terminal identification data with said program identification data; said central facility further includes means for storing a duplicate of said terminal specific encryption key; means for encrypting said code encryption key according to said terminal specific encryption key; and means for sending the encrypted code encryption key from said central facility to said terminal; and said terminal further further includes means for receiving the encrypted code encryption key from said central facility; and decryption means for decrypting said code encryption key according to said terminal specific encryption key.
Claim 6
Dependent Claim
174 words
The video system of any one of claims 1-4 wherein: said terminal further includes means to store terminal identification data and a terminal specific encryption key; and means to send to said central facility said program identification data and said terminal identification data, said central facility further includes means for providing a session encryption key; means for encrypting said session encryption key according to said terminal specific encryption key; means for sending the encrypted session encryption key from said central facility to said terminal; means for encrypting said code encryption key according to said encrypted session encryption key; and means for sending the encrypted code encryption key from said central facility to said terminal; and said terminal further includes means for receiving the encrypted session encryption key from said central facility; decryption means for decrypting said session encryption key according to said terminal specific encryption key, means for receiving the encrypted code encryption key from said central facility; and decryption means for decrypting said code encryption key according to said session encryption encryption key.
Claim 7
Dependent Claim
60 words
The system of claim 5 or 6 wherein said terminal includes means to encrypt said terminal identification data according to said terminal specific encryption key, and means to send unencrypted terminal identification data and encrypted terminal identification data to said central facility, and said central facility includes means to compare unencrypted and encrypted terminal identification data to authenticate terminal identity.
Claim 8
Independent Claim
30 words
The system of any one of claims 5-7 wherein said central facility further includes means for generating billing data based on said terminal identification data and said program identification data.
Claim 9
Dependent Claim
30 words
The video system of any one of claims 1-8 wherein said video program means is a means located at said terminal for playing a video recording medium storing said program.
Claim 10
Dependent Claim
57 words
A video recording medium storing a video program including a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video signal according to said random digital code.
Claim 11
Dependent Claim
54 words
The medium of claim 10 wherein a plurality of code encryption keys are used for one program, and wherein a desired code encryption key is selected from said plurality of code encryption keys in accordance with code encryption key identification data corresponding to the random digital code encrypted with said desired code encryption key.
Claim 12
Dependent Claim
62 words
The medium of claim 10 or 11 wherein said second field has a vertical blanking interval containing both a random digital code encrypted according to a code encryption key and program identification data, and is followed by a third field containing an unintelligible video signal previously transformed from an intelligible video signal according to said random digital code of the second field.
References Cited (Backward Citations)
No citation records indexed.
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